Communication Solutions

Yours Truly met late last August with Cisco’s Director of Service Provider Solutions Marketing, Mark Milinkovich. He revealed that Cisco was about to unveil a new, small form factor version (a 4-slot, single-shelf) of the incredibly powerful Cisco CRS-1 Carrier Routing System, a device normally found at the Internet’s core. (The CRS-1 portfolio also includes 8-slot and 16-slot versions.)

 

How powerful you ask? How about support for moving 40 gigabits per second (Gbps) per slot through Packet-over-SOnet (PoS), Dense Wave Division Multiplexing (DWDM) and Ethernet interfaces?

 

“Cisco has also announced that the architecture will be upgradeable to 100 gigabits per second IP processing capability per wavelength when that technology becomes available,” says Milinkovich. “However, the first interface we’re seeing being tracked from a standards perspective would be 100 Gbps Ethernet.”

 

The reason for all of this capacity stems from both the need to converge next-generation and legacy networks, plus the additional immense bandwidth requirements made necessary in the next-gen network by what Cisco calls “the Empowered Consumer” and “the Connected Life.”

 

 

The Empowered Consumer is a direct result of increasingly less expensive broadband and the bi-directional nature of packetized communications.

 

“In the old days,” says Cisco’s Milinkovich, “the dynamic was from the provider to the user. Viewers passively watched and heard broadcast programming. With the rise of more sophisticated cable TV systems, the network was a bit more responsive and the user could engage in some simple transactions with the provider, such as picking a movie in a Video on Demand [VoD] scenario. As the next generation network advances, the user can experience greater levels of personalization and socialization via the network, and can participate in community services. Ultimately, the user will be greatly empowered, capable of completely customizing his or her communications environment and not merely participating but actually creating and/or remixing existing content.”

 

To support such increasing user interactivity in the network, both additional network “smarts” and bandwidth are needed. Moreover, the total empowerment of the consumer ultimately leads to Cisco’s concept of the “the Connected Life” which places an even greater demand on bandwidth.

 

 

“Really, what we see as ‘the Connected Life’ are many things from a trend perspective, ranging from an increase in personalization to the ability to access any information or entertainment wherever and whenever they want it,” says Milinkovich. “In such a world you can find you kid’s GPS location on your TV, download the latest tunes, watch TV on the train while simultaneously programming your digital video recorder [DVR] for the evening, schedule a meeting, conduct a telepresence meeting, work from home, answer video calls on your TV, and so forth.”

 

“This is a visualization about the impact of the empowered consumer,” says Milinkovich. “Again, harking back to the concept of ‘personalization’, both of these ideas are intertwined. The empowered consumer has gone from passively watching TV to now being able to do VoD for movies, etc. With YouTube and with various other facilities such as FastWeb in Italy, people are actually posting their own Web and video material up on the Internet themselves. YouTube now has in excess of 100 million video downloads per day. Putting that into perspective, we’re really seeing that there’s a dynamic two-way phenomenon happening in the industry, Thanks to video the impact of the personalization is much greater—because video provides a visual impact. Video is causing major changes in the industry.”

 

“Both consumers and service providers are now looking at customization and personalization as defining the kind of experience the provider should be delivering, says Milinkovich. “It’s this experience that reduces the churn rate, increases the value proposition of the services and really holds consumer interest, thus keeping consumers on board.”

 

“Service provides have responded by changing both their business practices and technologies in several different ways,” says Milinkovich. “First they went beyond examining broadcast parameters to examine fundamentals such as Quality of Service [QoS], and network responsiveness in terms of being able to deliver video. Now they’re looking at Web portals, co-branding, and bidirectional calls, using bandwidth to help resolve issues posed by the empowered consumer.”

 

“As we start to see the abilities of the consumer rise, we start to see the huge impact that video will have and currently has, particularly in the U.S. but also in other markets worldwide,” says Milinkovich. “Let’s look at a typical home with one high definition TV, which, using MPEG-2 compression, uses around 19 megabits per second per stream. The home is also expected to have one standard definition TV, so that uses somewhere between 1.5 and 3 megabits per stream. Naturally, there will be two personal video recorders (PVRs): one streaming to the parents and one being watched by the children at any one time, or vice versa. Then there’s the bandwidth occupied by an IP call, plus a high speed data interconnect for Internet access. The total bandwidth capacity requirements for each such typical home is thus in the range of 25 to 50 megabits per second. More importantly, in terms of the calculations of the actual content of what’s going over those connections, they’re in excess of a terabit per month. That is, if they view a 90 minute movie in combination with the other things going on, then you’re looking at a terabit worth of content being delivered per home each month.”

 

Milinkovich muses: “Let’s put this bandwidth into perspective: 20 such homes would consume as much bandwidth traffic as what the entire Internet backbone carried in 1995!”

 

“When you combine the bandwidth capacity needed in such a network,” says Milinkovich, “plus the intelligence in the network necessary to deliver a level of personalization to the empowered consumer, you start to see unique trends in the industry that are pushing video into becoming a new opportunity in the marketplace.”

 

 

This leads us back to the CRS-1, a platform that can help bring such advanced services to consumers.

 

“When we first announced the CRS-1 in December 2004,” says Milinkovich, “we saw the need for a high capacity core router, particularly when carriers were looking at next-generation networks converging with many different types of legacy transport systems such as ATM. Now that Cisco’s IP NGN vision is starting to come to fruition, with CRS-1 systems owned by over 60 major customers globally—such as China Telecom, British Telecom, Japan’s SoftBank BB and most recently by KT, Korea’s leading service provider, for its KORNET backbone network solution—our announcement is very significant to the industry at large because it means that carriers and providers can drive the CSR-1’s high reliability and video awareness directly down into major hub locations, as well as smaller Class 3 and Class 4 central office applications.”

 

“Currently, the CRS-1 is the premier product in the Internet core today,” says Milinkovich. “There are several key aspects of the CRS-1’s technology. At a high level, it offers tremendous service flexibility, supporting intelligent video distribution—specifically, multicast. Then there’s the CRS-1’s ability to provide secure virtualization, which allows for separation in the platform itself between different elements such as entertainment and business grade services.”

 

The CRS-1 platform’s scalability and efficiency was greatly enhanced with Cisco’s introduction in December 2005 of IP over DWDM [Internet Protocol over Dense Wave Division Multiplexing], which enables seamless integration between the IP layer and the DWDM layer.

 

Milinkovich elaborates: “With our IP over DWDM technology integrated directly onto the CRS-1, the overall capex is lowered in excess of 50 percent and the capacity increased to 40 gigabits per second per wavelength directly from the CRS-1.”

 

The CRS-1 supports 40 Gbps per slot capacity in each direction in all form factors. Hardware scalability depends upon two major building blocks—line card shelves and fabric card shelves. The CRS-1 can be deployed in two configurations: a single-shelf system and a multi-shelf system. A single-shelf system is built from a single line card chassis, available in 4, 8, or 16 slots. A Cisco multi-shelf system is built by interconnecting multiple line card shelves using one or more fabric shelves.

 

Thus, the new 4-slot CRS-1 handles a total of 320 Gbps to 640 Gbps (depending on whether it’s a single or multiple shelf/chassis system), which is suitable for small POPs. The 8-slot version can deal with 640 Gbps to 1.2 Tbps depending on the number of chassis/shelves, large enough to serve medium-sized POPs. A 16-slot model or a multi-chassis system can handle from 1.2 Tbps to an incredible 92 Tbps, giving it the capacity to tame so-called “mega POPs”. A 92 Tbps system can be achieved in a multi-chassis system by assembling 72 line card shelves and eight fabric shelves all operating as a single system.

 

“This scalability partly results from our observations that, because of the increase in bandwidth demand and the pressures in the industry on capex dollars, there’s a greater need for longer depreciation times and values,” says Milinkovich. “Typically, we’ve seen depreciation intervals in the area of from three to five years. Now we’re pushing the envelope to seven to ten years, where we see the multi-chassis fabric being able to scale from the single chassis straight up to a 92 terabits per second multi-chassis system, which really delivers the scalability over a longer depreciation cycle that the carriers like to see today.”

 

Cisco’s CRS-1 is also said to be the first carrier router offering continuous system operation, allowing for upgrades while the system continues to run and generate revenues.

 

“The CRS-1’s continuous system operation is made possible by Cisco’s IOS-XR operating system, a self-healing, distributed operating system designed for always-on operation,” says Milinkovich. “We see that continuous systems operation really meets the needs of service providers today. You now see the integration of voice, video and data on one common converged infrastructure, and the ability to have reduced maintenance windows so that one can upgrade software without rebooting the system—in other words, being able to introduce ‘hitless’ hardware and software upgrades—is really a hard requirement now. Providers can’t afford to bring down a network to perform a maintenance upgrade. They must be able to do it in real time.”

 

“Our new 4-slot system now extends the capabilities of the CRS-1 into smaller regional hub sites as well as Class 3 and Class 4 central offices to deliver the capacity that’s needed for the consumer video experience and to deliver the intelligence that’s needed to manage that video end-to-end,” says Milinkovich. “Specifically, it extends the IP and MPLS core reach, so we can now extend 40 gigs per card slot capacity into smaller POPs [Points of Presence]. This platform has all of the operating system features I mentioned earlier, such as continuous operation, multicast scalability and the intelligence in the system.”

 

“The four-slot system fits into a standard 800 mm-deep enclosure,” says Milinkovich. “This is important because the CRS-1 platform currently ships with its own rack. Because of its high capacity and its scalable growth potential, we ship it with its own four-post rack system. The four-slot system fits into 19-inch racks and can be used in datacenter applications situated in such emerging markets such as Russia and Saudi Arabia, and it can yield the scale and connectivity into a typical central office without requiring any kind of special mounting mechanisms.”

 

“Investment protection across the card slots is maintained among each and every one of the CRS-1s,” says Milinkovich, “Aside from the multiservices card, where all the IP processing happens, the line cards can make up about 60 percent of the overall system cost. All of these cards are common among the entry level unit, straight up to the biggest systems. This reduces opex as well as capex through common service provisioning, common sparing, and a common operating system, so methods and procedures are identical, and it really allows a distributed system to scale up easily and cost effectively.”

 

“The CRS-1, with its high availability and its intelligence, also integrates with devices at the network services edge, thanks to the commonality of the Cisco portfolio,” says Milinkovich. “For example, take the Cisco 7600 router, which is very popular within both the wireline and cable segments for delivering high-IP packet processing capability and high-density gigabit Ethernet for carrier Ethernet applications. Then there’s the Cisco 10000, which provides the intelligence at the network edge for the broadband subscriber area, where it targets narrowband interfaces, typically DS0 or T-1 interfaces, and then that can be aggregated up into larger pipes in the core via the CRS-1. Additionally, there’s the Cisco XR 12000, which enables a multi-services edge, so both narrowband, Frame Relay, ATM, plus IP MPLS can all aggregate up into, say, a four-slot CRS-1.”

 

“By extending the 40 gigabit capability per card slot, as well as moving equipment into regional sites, we’re really seeing the ability now to foster the capacity needed as well as the intelligence for video applications,” says Milinkovich. “For example, managing broadcast TV and Video on Demand oversubscription with Connection Admission Control [CAC].”

 

So, as the world falls in love with broadband video and other bandwidth-gobbling services, the “fiber glut” will finally disappear and the world’s carriers will increasingly relay on such super-powerful and video-savvy routing platforms as Cisco’s highly scalable CRS-1.